BUG #6187: Select query stuck

The following bug has been logged online:

Bug reference: 6187
Logged by: Bhavesh Dangi
Email address: dangi(dot)bhavesh86(at)gmail(dot)com
PostgreSQL version: PostgreSQL8.0.1
Operating system: i686-pc-linux-gnu
Description: Select query stuck
Details:

Hello,

Here the problem is SELECT query takes a lot of time(in days) to return a
result than expected time and sometimes it stop to responding. Its totally
hang. We are suffering from last 1 years by having this issue. If it will
happen then we finding that query from pg_stat_activity and cancel it but
that is not a solution of problem.
We also found that almost SELECT queries are stuck. We are also continuous
performing veccumdb before 2 billion transactions.
I hope that you will be provide some way to solve it.

Thanks & Regards,
Bhavesh Dangi